The present invention addresses the technique by which public networks control access to features and services by subscribers. More specifically, the invention addresses the access of features from a hierarchical switch by subscribers based on which organization, if any, the subscriber is a member.
Private branch exchanges are typically utilized by groups of subscribers located in one geographic area, such as by employees of a company located at a building or campus. While PBXs support a relatively wide range of subscriber services and features, the features are provided only to subscribers connected directly to the PBX. This provides the subscribers with enhanced features such as abbreviated dialing of other subscribers also served by the same PBX. However, a subscriber served by a PBX is normally required to dial a complete public telephone system number in order to reach another employee of the same company not served by the same PBX. Thus, PBXs have significant limitations associated with the control of subscriber features.
Centrex systems are typically utilized by groups of subscribers, such as employees of a company, and provide features supported by equipment located integral with a local telecommunication switch. Thus, Centrex support is provided by the local exchange carrier (LEC) for its subscribers. Although Centrex systems support a relatively wide range of subscriber services and features, the subscribers are limited in their choice of service providers. Because Centrex services are based on local switch control, network wide solutions to controlling access to features are difficult to implement and administer.
While increased capabilities of consumer premises equipment (CPE) have added to the way features can be accessed by subscribers, such facilities still have limitations. Certain features do not lend themselves to implementation by CPE. For example, a network parameter associated with a call may be required in order to provide an enhanced feature for the subscriber. If the network parameter is not sent to the CPE, it will be apparent that the CPE is incapable of implementing a feature which requires access to this parameter. Since CPE is adapted to individual subscriber control, features which depend on group affiliations are not suited for implementation by the CPE.
Thus, a need exists for an improved public network solution which will permit group affiliations of subscribers to be used in the delivery of features to subscribers.